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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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ALASKAN GLACIER STUDIES
The advancing glaciers in Prince William Sound are also of variable sizes; but here the largest, Columbia and Valdez, seem to have begun to advance in 1907-08, long before the smaller College Fiord and Unakwik Inlet ice tongues. Here, nine or more glaciers, the large Harvard, Yale, and Meares Glaciers, and the smaller, Wellesley, Vassar, Biyn Mawr, Smith, Radcliffe, Barnard, and possibly other small ones, all began to advance together in 1909-10. This absence of relation between size and period of advance, and the lack of spasmodic transformation to activity with rapid return to stagnation, observed in Yakutat Bay, suggests that the advances now in progress in tfria part of Prince William Sound are probably climatic.
The following table l shows the precipitation record from the nearest stations. It also suggests that the glacier advances in College Fiord and Unakwik Inlet are climatic. The data is given both in snowfall and in total precipitation (rainfall plus melted snow), and is arranged by years from July 31 to July 31, so that the snowfall of the winters of two calendar years appears together, that is by snow years.
TABLE SHOWING PRECIPITATION FROM (1) FOBT LISCUM NEAR VALDEZ, (2) SUNRISE
ON TURNAGAIN ARM, (3) EJENAI ON COOK INLET, ALL AT SEA-LEVEL,
AND (4) COPPER CENTER, 1000 FEET ABOVE SEA-LEVEL
Van*	Total Precipitation, in inches	Snowfall, in inches			
	Port Liscum	Fort Liscum	Sunrise	Eenai	Copper Center
190102	78.67	834.4	------	82.3	.
190208	96.26	671.1	------	109.1	36.5
190804	57.88	255.9	89.4	92.6	47.1
190405	69.58	187.8	123.4	40.1	25.5
190506	72.62	338.5	112.1	48.7	64.1
190607	72.81	299.0	83.8	47.1	28.8
190708	91.85	447.2	158.9	------	31.5
190809	78.52	888.7	85.0	------	27.0
190910	70.29	458.5	132.2	------	33.0
Mean	75.77	870.1	112.1	60.8	36.6
It might be thought that the increase in snowfall at Fort Liscum (a) from 334 inches in 1901-1902 to 671 inches in 1902-1903, an augmentation of 337 inches or 28 feet, or (b) from 299 inches in 1906-1907 to 447 inches in 1907-1908, an increase of 148 inches or 12 feet, or (c) from 338 inches in 1908-1909 to 458 inches in 1909-1910, an increase of 120 inches or 10 feet, would be quite adequate to account for the advance of the eight glaciers in College Fiord. To this there are two possible objections.
First, Fort Liscum, the nearest of the U. S. Weather Bureau observatories, is nearly 50 miles from College Fiord (PI. XCHI); and it is by no means certain that the climatic oscillations are similar and synchronous. Unfortunately the other places where precipitation records are kept, to the north and southwest of College Fiord, are in regions of dissimilar climate and the records are incomplete, though the table just quoted shows
1 Martin, Lawrence, Some Features of Glaciers and Glaciation in the College Fiord, Prince William Sound, Alaska, Zeitschrift ftlr Gletscherkunde, Band VII, Heft 5, 1913, pp. 28-31.